[awiesenhofer]

Since you mention a mi band, gadgetbridge should have you covered - never tried to export data myself though.

https://gadgetbridge.org/

https://codeberg.org/Freeyourgadget/Gadgetbridge/wiki/Data-E...

[mdrzn]

Cheers, tried exporting using something similar like 4 years ago on a MiBand 2 and it was soooo much data unformatted. I'll check it out again.

[vanous]

The data is pretty much as the band provides it. Mostly in one minute resolution, giving you steps, heart rate, "intensity" (this could somehow be translated to calories). From this, you can calculate your agregated your stats...